ASHRAE Standard 241. Think of it as
a Clean Air Act for the indoors.

In 1963, the Clean Air Act marked a historic milestone by setting crucial regulation to combat outdoor air pollution, representing a significant stride towards fostering a healthier environment for all. This landmark legislation, however, primarily focused on addressing pollutants in the outdoor realm. Given the fact that individuals typically spend approximately 90% of their time indoors, a significant aspect of air quality regulation remained overlooked.

Recognizing this oversight, the introduction of ASHRAE Standard 241 represents a commendable development. This latest standard not only acknowledges the importance of indoor air quality but also establishes clear and rigorous requirements to ensure that the air we breathe indoors reduces the risk of disease transmission, thus fortifying our collective commitment to fostering clean and healthy air for all.

What is ASHRAE?

ASHRAE stands for the American Society of Heating, Refrigerating and Air-Conditioning Engineers. It is a professional global organization that focuses on advancing the arts and sciences of heating, ventilation, air conditioning, and refrigeration to serve humanity and promote a sustainable world.

What is ASHRAE Standard 241?

ASHRAE Standard 241, officially titled “Control of Infectious Aerosols,” establishes minimum requirements aimed at reducing the risk of disease transmission through exposure to infectious aerosols in various building types. The implementation of this standard brings numerous benefits to occupants and promotes healthier environments.

In response to the valuable insights gained from the COVID-19 pandemic, ASHRAE Standard 241 acknowledges the limitations of conventional ventilation systems in addressing airborne pathogens. Through the implementation of rigorous air filtration and cleaning requirements, this standard is designed to reduce the risk for infectious aerosol transmission within buildings. The ultimate goal is to create indoor environments that prioritize safety and well-being, ensuring healthier space for all occupants.

ASHRAE Standard 241 represents new and stricter requirements for indoor air quality compared to the more lenient standards previously set forth by ASHRAE 62.1.

What are the Key Components of ASHRAE Standard 241?

ASHRAE Standard 241 introduces key groundbreaking features for building owners to maintain a healthier environment in hopes to lower the risk of disease transmission by reducing the infectious aerosols.

Some of the key components of ASHRAE Standard 241 include:

Infection Risk Management Mode (IRMM)

This mode applies during identified times of elevated airborne disease transmission risk, utilizing compliant air filtration systems for enhanced air output.

Equivalent Clean Airflow Rate

The standard sets a target for 25 space types for the equivalent clean airflow rate per occupant (ECAi) that air cleaning and HVAC devices must produce in order to reduce the risk of airborne infection.

Filtration and Air Cleaning Technology

Technologies such as HEPA filters, UV lights and other technologies should meet the test requirement to establish effectiveness and safety.

Building Readiness Plan

The standard includes a plan that outlines procedures for evaluating both existing and new HVAC and air filtration systems, ensuring proper function and delivery of clean air.

What does ASHRAE Standard 241 Mean for Commercial Air Purification?

ASHRAE Standard 241 sets a new benchmark for indoor air quality, especially in the context of infectious aerosol control.
Commercial spaces will need to ensure their air purification systems meet or exceed these standards, leading to a potential
surge in upgrades or replacements of outdated systems.

Experts from the Johns Hopkins Center for Health Security are calling on states to create legislation aimed at improving indoor air quality in public spaces—and giving them the tools to do so through the Model State Indoor Air Quality Act.

Achieve ASHRAE Standard 241
Compliance With AirBox Air Cleaners

AirBox air cleaners are specifically engineered to abide by the strict indoor air quality requirements set forth by ASHRAE Standard 241.

By harnessing advanced air purification technologies, AirBox systems effectively capture over 99.9% of tested airborne contaminants, including infectious aerosols that can pose significant health risks. Tests are available under request.

AirBox air cleaners apply to a wide range of building types, including corporate offices, construction sites, schools, and healthcare facilities.

Why Choose AirBox?

Precision Engineering

Every AirBox air cleaner is crafted to deliver optimal clean airflow rates, ensuring that spaces using air cleaning technology, whether commercial or residential, are using devices compliant with the ASHRAE Standard 241.


Recognizing the diverse needs of different indoor environments, AirBox offers a range of products and filtration tailored for various spaces, from compact units for classrooms and offices to robust systems for larger commercial areas.

Recreational Spaces

Gymnasiums and recreational facilities rely on AirBox to provide cleaner and healthier air to their guests, fostering a healthy public environment.

Ready to assure your air
cleaning system’s compliance?

Partnering with a trusted name like AirBox ensures that you’re not only compliant with industry
standards like ASHRAE Standard 241 but also providing the best environment for occupants. 

With AirBox, you’re not just installing an air cleaner; you’re making a statement about your
commitment to health, safety, and excellence.